Energy of 1000 J is spent in increasing the speed of a flywheel from 30 rpm to 720ppm, find the moment of inertia of the wheel

Energy of 1000 J is spent in increasing the speed of a flywheel from 3

1.	Energy of 1000 J is spent in increasing the speed of a flywheel from 30 rpm to 720ppm, find the moment of inertia of the wheel
Answer» Solution :`omega_(1)=30 rpm= 2pi xx(30)/(60)"rad" s^(-1)= pi "rad" s^(-1)` `omega=720 rpm= 2pi xx(720)/(60) "rad" s^(-1)=24 pi "rad"` Change in kinetic energy `DeltaKE=(1)/(2)(omega_(2)^(2)-omega_(1)^(2))` `I=(2xxDeltaKE)/((omega_(1)^(2)-omega_(1)^(2)))=(2xx1000)/((24pi)^(2)-(pi)^(2))` `I=(2000)/(25 pixx23 pi)` REMEMBER : `a^(2)-b^(2)=(a+b)(a-b)` `I~~0.35 kg m^(2) and pi^(2)=10`